1. Field of the Invention
This invention relates to a radiation resistant electric wire and a radiation resistant electric cable, which is formed by use of a fire retardant resin composition having excellent radiation resistance.
2. Description of the Related Art
Electric wires or cables for use in nuclear power stations, radioactive waste disposal facilities, breeder reactors or the like are exposed to radiation in a normal use environment, and therefore required to be resistant to radiation. At present, an ethylene propylene rubber, polychloroprene rubber, chlorosulfonated polyethylene or the like is used for cable insulation and sheath polymers being used in nuclear power stations or the like, and a general method to make the cable insulation and sheath polymers resistant to radiation is to add therein a process oil or an antioxidant such as an aromatic system.
In recent years, however, the electric wires or cables have been required to be further resistant to radiation so that their lives are prolonged or they are applied to nuclear fusion reactor peripheral materials and the like. In prior art, the amounts of the aromatic process oil and the antioxidant have been increased.
Refer to JP-A-05-125251 and JP-A-10-120792, for example.